Imaging device and imaging system

Abstract

An imaging device capable of reporting more reliably an occurrence of trouble is provided. The imaging device of the present disclosure includes an imaging sensor configured to generate image data, a diagnosis circuit configured to perform diagnosis processing for the imaging sensor and an output circuit configured to output a flag signal corresponding to a result of the diagnosis processing, wherein the flag signal is set to a ground level signal in response to the result of the diagnosis processing indicating an error.

What is claimed is: 
     
       1. An imaging device, comprising:
 a pixel array including a plurality of pixels, each of the plurality of pixels being configured to generate a pixel signal based on a first power supply voltage; 
 a diagnosis circuit configured to perform diagnosis processing for the imaging device; and 
 an output circuit configured to output a flag signal corresponding to a result of the diagnosis processing, wherein the flag signal is set from a first level signal to a ground level signal if the result of the diagnosis processing indicates an error, 
 wherein a startup sequence of the imaging device comprises:
 (a) causing the first power supply voltage to change from a ground level to a second level, 
 (b) causing a start-up test to be performed after the causing of the first power supply voltage to change in (a), and 
 (c) causing the flag signal to change from the ground level signal to the first level signal if a result of the start-up test indicates no error. 
 
 
     
     
       2. An imaging device according to  claim 1 , further comprising:
 a controller configured to control the startup sequence of the imaging device. 
 
     
     
       3. The imaging device according to  claim 1 , wherein the startup sequence further comprises:
 (d) causing the flag signal to keep the ground level signal if the result of the start-up test indicates an error. 
 
     
     
       4. The imaging device according to  claim 1 , wherein a clear signal received by the imaging device changes from a low level to a high level after the causing of the first power supply voltage to change in (a) of the startup sequence. 
     
     
       5. The imaging device according to  claim 4 , wherein the clear signal received by the imaging device changes from the low level to the high level between the causing of the first power supply voltage to change in (a) and the causing the flag signal to change in (c) in the startup sequence. 
     
     
       6. The imaging device, according to  claim 1 , wherein the flag signal is changeable between the ground level signal and the first level signal. 
     
     
       7. The imaging device according to  claim 6 , wherein the flag signal is set to the first level signal if the result of the diagnosis processing indicates a proper operation. 
     
     
       8. The imaging device according to  claim 1 , wherein the output circuit is configured to be coupled to a second power supply voltage, which is different from the first power supply voltage. 
     
     
       9. The imaging device according to  claim 8 , wherein the output circuit is configured to output the ground level signal if the second power supply voltage is not supplied to the output circuit. 
     
     
       10. The imaging device according to  claim 8 , wherein the start-up test is performed after the second power supply voltage changes from a ground level to a third level. 
     
     
       11. The imaging device according to  claim 8 , wherein the diagnosis circuit is configured to be coupled to a third power supply voltage, which is different from the first and second power supply voltages. 
     
     
       12. The imaging device according to  claim 11 , wherein the start-up test is performed after the third power supply voltage changes from a ground level to a fourth level. 
     
     
       13. The imaging device according to  claim 11 , wherein the output circuit is configured to output the ground level signal if the third power supply voltage is not supplied to the diagnosis circuit. 
     
     
       14. The imaging device according to  claim 1 , wherein the flag signal is output through a dedicated terminal. 
     
     
       15. The imaging device according to  claim 1 , wherein:
 the imaging device is mounted on a vehicle, and 
 the startup sequence of the imaging device starts if an accessory-on operation of the vehicle is detected. 
 
     
     
       16. The imaging device according to  claim 1 , wherein:
 the pixel array includes a dummy circuit configured to generate a dummy signal, and 
 the diagnosis processing is performed based on the dummy signal. 
 
     
     
       17. The imaging device according to  claim 16 , wherein:
 the dummy signal is converted to digital data by an analog-to-digital converter, and 
 the diagnosis processing is performed based on the digital data. 
 
     
     
       18. A vehicle comprising:
 an imaging unit that includes an imaging device, the imaging unit being configured to generate image data; 
 an outside-vehicle information detecting unit configured to detect an object in an environment based on the image data; and 
 a vehicle control unit configured to control a driving unit for a driver assistance system of the vehicle based on information obtained by the outside-vehicle information detecting unit, 
 wherein the imaging device comprises:
 a pixel array including a plurality of pixels, each of the plurality of pixels being configured to generate a pixel signal based on a first power supply voltage; 
 a diagnosis circuit configured to perform diagnosis processing for the imaging device; and 
 an output circuit configured to output a flag signal corresponding to a result of the diagnosis processing, wherein the flag signal is set from a first level signal to a ground level signal if the result of the diagnosis processing indicates an error, 
 
 wherein a startup sequence of the imaging device comprises:
 (a) causing the first power supply voltage to change from a ground level to a second level, 
 (b) causing a start-up test to be performed after the causing of the first power supply voltage to change in (a), and 
 (c) causing the flag signal to change from the ground level signal to the first level signal if a result of the start-up test indicates no error, and 
 
 wherein the vehicle control unit is configured to restrict a function of the driver assistance system in response to the flag signal. 
 
     
     
       19. The vehicle according to  claim 18 , further comprising:
 a controller configured control the startup sequence of the imaging device. 
 
     
     
       20. The vehicle according to  claim 18 , wherein the vehicle control unit is configured to notify information to an occupant of the vehicle in response to the flag signal. 
     
     
       21. The vehicle according to  claim 18 , wherein the driver assistance system comprises at least one of:
 a collision avoidance system, 
 a collision-damage mitigation system, 
 a cruise-control system, 
 a collision warning system, and 
 a lane-departure warning system. 
 
     
     
       22. The vehicle according to  claim 18 , further comprising:
 an electronic control unit configured to cause the imaging device to start the startup sequence in response to an accessory-on operation of the vehicle.